<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>卡券效果</title>
    <style>
        body {
            background-color: gainsboro;
        }

        .coupon {
            width: 300px;
            height: 100px;
            line-height: 100px;
            margin: 50px auto;
            text-align: center;
            position: relative;
            background: radial-gradient(circle at right bottom, transparent 10px, #ffffff 0) top right /50% 51px no-repeat,
                radial-gradient(circle at left bottom, transparent 10px, #ffffff 0) top left / 50% 51px no-repeat,
                radial-gradient(circle at right top, transparent 10px, #ffffff 0) bottom right / 50% 51px no-repeat,
                radial-gradient(circle at left top, transparent 10px, #ffffff 0) bottom left / 50% 51px no-repeat;
            filter: drop-shadow(2px 2px 2px rgba(0, 0, 0, .2));
        }

        .coupon span {
            display: inline-block;
            vertical-align: middle;
            margin-right: 10px;
            color: red;
            font-size: 50px;
            font-weight: 400;
        }
    </style>
</head>

<body>
    <p class="coupon">
        <span>200</span>优惠券
    </p>

    <p class="coupon">
        <span>200</span>优惠券
    </p>

    <p class="coupon">
        <span>200</span>优惠券
    </p>
</body>

</html>